Wyniki wyszukiwania - BazTech

Ograniczanie wyników

1 Polish Journal of Ecology

1 1998

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Long term effects of liming in a humic lake : ecosystem processes, biodiversity, food web functioning (Lake Flosek, Masurian Lakeland, Poland)

Hillbricht-Ilkowska A., Dusoge K., Ejsmont-Karabin J., Jasser I., Kufel I., Ozimek T., Rybak J.I., Rzepecki M., Węgleńska T.

Polish Journal of Ecology

1998

Vol. 46, no 4

347-415

The chemical composition of water and bottom sediments, productivity and decomposition rates as well as the biodiversity and food web functioning (organic suspension, edible algae, bacterio-detrivores, herbivores, grazers, predators) in plankton and benthos were analysed in humuc, weakly acid, mid-forest lake surrounded by peatmoss Sphagnum (Lake Flosek, Masurian Lakeland, Poland) before and 1-4 and 20-23 years after application of powdered lime. Calcium content and pH in water and sediment raised permanently. High water quality variables were main-tained after liming (low production, algal biomass, chlorophyll and nutrient concentration, low release rate of phosphorus from the sediments). Decomposition rate of organic matter increased significantly. The species richness and diversity of algae, rotifers, crustacean and benthic invertebrates increased at least twice as well as the abundance of bacterio-detrivores in plankton (small rotifers) and benthos (chironomids) and herbivores (big daphnids, diaptomids) in plankton. The distinct succession in species composition was observed in many taxa. The predators like larvae of Chaoborus, cyclopids and predatory rotifers became very abundant after 20 years since liming. No evident peatmoss mat spreading over the lake table has been observed since liming but also no detrimental effect on peatmoss surrounding the lake. It was concluded that the moderate liming affects first of all the biodiversity of lake biota then it stimulates the mobilisation of the lake which eventually lead to the greater and more stable complexity of trophic links. The species-rich and top-down controlled food web was installed in the limed lake without interfering with high quality of lake waters (low-productive, high-transparent) and unique, natural values of its surroundings.However, a slight increase in nutrient concentration after 22-23 years was observed which could be related to more efficient recycling mechanism in lake (due to abundant big components in plankton and benthos) or to eutrophication.